In LTE Release 8/9 (R8/9) of a Long Term Evolution Advanced (LTE-Advanced) system, in order to measure quality of a channel and demodulate a received data symbol, a Common Reference Signal (CRS) is designed. User Equipment (UE) may measure the channel according to the CRS to determine to perform cell reselection and handover to a target cell. In addition, the quality of the channel may be measured in a connected state of the UE, and when the level of interference is relatively high, a connection may be disconnected at the physical layer through high-layer related radio link connection failure signalling. In LTE R10, in order to further increase an average spectrum utilization rate of a cell and an edge spectrum utilization rate of the cell as well as throughput of each UE, two reference signals are defined respectively: a Channel State Information Reference Signal (CSI-RS) and a Demodulation Reference Signal (DMRS). The CSI-RS is used for channel measurement, and by the measurement of the CSI-RS, a Precoding Matrix Indicator (PMI), a Channel Quality Indicator (COI) and a Rank Indicator (RI), which are required to be fed back to an evolved NodeB (eNB) by the UE, may be calculated. The DMRS may enable the UE to transparently receive downlink data without knowing a precoding weight applied at an eNB side, so that a load of a Physical Downlink Control Channel (PDCCH) may be reduced, and in addition, limitations of a codebook to the weight can be reduced. In addition, dynamic and transparent switching between Single User-Multiple Input Multiple Output (SU-MIMO) and Multiple User-Multiple Input Multiple Output (MU-MIMO) is supported by the DMRS, and DMRS-based interference estimation is supported, so that interference cancellation performance of a receiving side can be greatly improved.
In later R11, a New Carrier Type (NCT) is introduced. The introduced NCT mainly adopts an enhanced Physical Downlink Control Channel (ePDCCH) for the sending of a control channel, so that there is no compatible carrier control channel area as defined in R10. During original designing of a reference signal, the first four Orthogonal Frequency Division Multiplexing (OFDM) symbols are mainly considered to be used for a control channel area, and the first four OFDM symbols are unsuitable to carry various reference signals (except a CRS for demodulating a PDCCH). For DMRS enhancement, demodulation performance of a DMRS may be influenced by the limitations of a control channel during designing, but preliminary simulation shows that the performance of the DMRS is just slightly influenced, so that necessity in DMRS enhancement needs to be further researched. In a later discussion period of R11, in subjects under discussion about Coordinate Multiple Point Transmission (CoMP) and a heterogeneous network, it is necessary to provide more multiplexing factors for a CSI-RS to ensure orthogonality of the CSI-RS as much as possible under the deployment of special Transmission Points (TP) such as the heterogeneous network and a small cell. In addition, conventional CSI-RS resources are obviously insufficient due to the problems that a part of CSI-RS are required to be dedicated to interference measurement of Interference Measure Resources (IMR), and that different IMRs may be configured to different terminals and the like. Therefore, in discussion about evolution situations of gradual replacement of a compatible carrier with an NCT in early and later NCT periods, it is definitely necessary to design a CSI-RS pattern with a large multiplexing factor.
For the problem of a lack of a CSI-RS pattern with a large multiplexing factor in evolution situations of gradual replacement of a compatible carrier with an NCT and the like in a related technology, there is yet no effective solution.